Broadway Subway - Millennium Line Extension to Arbutus | U/C

[VancouverOfTheFuture]

Originally Posted by scottN

You can if the tube is big enough to fit the train and a platform inside it.

theoretically you could probably use a regular machine and then carve out the stations, like mining. though i don't know how realistic that is or cost effective. i am sure ground conditions would play a factor as well.

at some point you would need something above ground anyways.

[scottN]

Originally Posted by VancouverOfTheFuture

theoretically you could probably use a regular machine and then carve out the stations, like mining. though i don't know how realistic that is or cost effective. i am sure ground conditions would play a factor as well.

at some point you would need something above ground anyways.

I thought the crossrail project in London was boring tube for station platforms, but it turns out they actually mined out the caverns for the underground stations.

https://www.crossrail.co.uk/project/tunnelling/building-the-station-tunnels

[WarrenC12]

Originally Posted by scottN

I thought the crossrail project in London was boring tube for station platforms, but it turns out they actually mined out the caverns for the underground stations.

https://www.crossrail.co.uk/project/tunnelling/building-the-station-tunnels

Of course it's possible. Arguably it would have been a good use of money at Main, Cambie, and Granville. Oh well.

[cganuelas1995]

Originally Posted by scottN

You can if the tube is big enough to fit the train and a platform inside it.

But then you have to build something above ground for passengers to enter and leave the system.

[Jebby]

Originally Posted by WarrenC12

Of course it's possible. Arguably it would have been a good use of money at Main, Cambie, and Granville. Oh well.

Probably wouldn't be feasible given how shallow the stations are. I'm guessing you'd have to be on solid rock to be able to mine out a cavern for a station which seeing how shallow the stations are, is likely not possible.

[Vin]

Originally Posted by VancouverOfTheFuture

theoretically you could probably use a regular machine and then carve out the stations, like mining. though i don't know how realistic that is or cost effective. i am sure ground conditions would play a factor as well.

at some point you would need something above ground anyways.

You can't simply carve it out as the boring drilling machine comes with a shoring ability to lay concrete around the tunnel in place. Can't do that for a larger station with platforms, elevator and emergency stair wells, mechanical rooms, etc. The machine is also single-directional and won't carve to the sides. It would simply be cost effective to just excavate, build and then cover.

[jollyburger]

Originally Posted by WarrenC12

Of course it's possible. Arguably it would have been a good use of money at Main, Cambie, and Granville. Oh well.

How would it have been a good use of money?

12m tubes with stations built in:



https://www.jacobs.com/newsroom/innovation/emergence-of-small-footprint-underground-metro-stations

[officedweller]

To show relative sizes, here's the Vancouver City Centre Station excavation with a tunnel tube in place before it was crushed and removed:
http://www.seataf.com/blogs/canadaline/2007-03-26/images/KICX4426.jpg
http://canadalinephotos.blogspot.com/2007/03/

[Migrant_Coconut]

And stacked platforms are much less efficient than centre or side platforms - for one, you've got twice the riders going through one set of escalators.

[cganuelas1995]

Originally Posted by Migrant_Coconut

And stacked platforms are much less efficient than centre or side platforms - for one, you've got twice the riders going through one set of escalators.

Not to mention it makes single tracking a lot less practical in the event of maintenance or a track problem that needs resolving.

[aberdeen5698]

Originally Posted by jollyburger

12m tubes with stations built in:

To do that you've got to bore a 12m tunnel through the entire line, even between stations, and that would hugely increase the tunneling cost.

[jollyburger]

Originally Posted by aberdeen5698

To do that you've got to bore a 12m tunnel through the entire line, even between stations, and that would hugely increase the tunneling cost.

Yeah I didn't say I agreed with it

[Lexus]

2021, October 3

Untitled by Lexus LX570, on Flickr

[Changing City]

Originally Posted by Lexus

2021, October 3

Thanks for the picture. I walked down West Broadway yesterday, and that rotary piling machine was working, on a Sunday, so they're obviously trying to maintain progress.

[swimmer_spe]

Looks under construction there.

[MIPS]

It's amazing how much more open that side of the block looks now that those buildings are gone. If you didn't know that turning to your left revealed the downtown core you would swear this is some suburban station out in the valley.

[Jimbo604]

Photo source me

[WarrenC12]

I sure hope that that tunnel boring machine doesn't encounter any issues between there and Main/Kingsway area. It's going under a lot of existing buildings.

[VancouverOfTheFuture]

Originally Posted by WarrenC12

I sure hope that that tunnel boring machine doesn't encounter any issues between there and Main/Kingsway area. It's going under a lot of existing buildings.

does anyone here know the legal requirements for doing something like that? i imagine it must be challenging and require compensation, etc. and it could impact future developmental potential above i imagine.

[DKaz]

If they managed to bore under Yaletown with much deeper underground parking structures, I'm sure Broadway will be fine. They would have done their due dillegence before proceeding.